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subdivisions of the Carboniferous System

… in 1839, was subsequently termed Mississippian in 1870 as a result of work conducted by another American geologist, Alexander Winchell, in the upper Mississippi valley area. Eventually the overlying strata, the coal-bearing rocks originally described from Pennsylvania, were formalized as Pennsylvanian in 1891 by the paleontologist and stratigrapher Henry Shaler…

The type region for the Mississippian Subsystem lies in the central Mississippi Valley of the United States. Most of the formations representing the type sequence are found in Missouri, Iowa, and Illinois. The Kinderhookian Series includes the Hannibal Formation and the Chouteau Group.…